Mandatory IPv6 callbacks introduced in Steam by Valve Corporation around 2021 to test who uses IPv6. The service is active in the Steam client at the start, as well as explicitly for different products with the Unreal-Engine. There is no benefit for users.
| Title | Publisher | Released | Steam APP ID: | |
 | 7 Days to Die | The Fun Pimps Entertainment LLC | 2013 | 251570 |
 | ACE COMBAT™ 7: SKIES UNKNOWN | Bandai Namco Entertainment | 2019 | 502500 |
 | Alien Rage - Unlimited | CI Games S.A. | 2013 | 217920 |
 | Ancestors: The Humankind Odyssey | Private Division | 2020 | 536270 |
 | ASTRONEER | System Era Softworks | 2016 | 361420 |
 | Bee Simulator | Nacon S.A. | 2020 | 914750 |
 | BIOMUTANT | THQ Nordic GmbH | 2021 | 597820 |
 | Bravery and Greed | Team17 Digital Ltd | 2022 | 943370 |
 | Call of the Sea | Raw Fury Games | 2020 | 1042490 |
 | CODE VEIN | Bandai Namco Entertainment | 2019 | 678960 |
 | Contrast | Focus Entertainment | 2013 | 224460 |
 | Coral Island | Humble Games | 2023 | 1158160 |
 | Crime Boss: Rockay City | 505 Games S.p.A. | 2024 | 2933080 |
 | Days Gone | Sony Interactive Entertainment LLC | 2021 | 1259420 |
 | Deadlight Director’s Cut | Deep Silver | 2016 | 423950 |
 | Destroy All Humans! | THQ Nordic GmbH | 2020 | 803330 |
 | Devil’s Hunt | Fulqrum Publishing, Ltd. | 2019 | 887720 |
 | Dolmen | Prime Matter | 2022 | 831050 |
 | DRAGON QUEST TREASURES | SQUARE ENIX CO., LTD. | 2023 | 2021210 |
 | DRAGON QUEST® XI: Echoes of an Elusive Age™ - Digita... | SQUARE ENIX CO., LTD. | 2018 | 742120 |
